In general, a solid state drive (SSD) that is mounted with a memory cell array configured using a NAND-type non-volatile element has attracted attention as an external storage device that is used for a computer system. A flash memory has advantages in a high-speed operation and a lightweight body over a magnetic disk device.
The SSD executes a process called a garbage collection that records update data in blocks of the memory cell array page by page and generates available blocks by performing reclaiming operation, when the available blocks are exhausted.